Jessie wants her science fair project to make a difference. So when she gets the chance to test a local creek for pollution, she can't wait to get started. But when things start going wrong with her experiment, Jessie and her siblings don't just have an experiment to investigate, they have a mystery to solve!

Can the Aldens figure out who's responsible for the bad press before the center gets shut down for good? Henry, Jessie, Violet, and Benny are excited to learn more about raptors when they volunteer at a rehab center for wild birds. But not long after they arrive, a series of strange events makes it seem like someone might be trying to sabotage the center. Who could the culprit be, and why would they want to cause trouble for injured birds?